Bone metabolism appears to change before patients show clinical signs of rheumatoid arthritis and could ultimately serve as an early marker of disease, based on a study of 79 patients.
“There appears to be an alteration in bone metabolism parallel to inflammation and autoimmunity in the asymptomatic preclinical phase of RA, which may reflect the beginning of joint destruction,” according to Dr. Dirkjan van Schaardenburg, a rheumatologist at Jan van Breemen Institute in Amsterdam, and his coinvestigators.
They found significantly increased average levels of only P1NP (procollagen type I intact N-terminal propeptide) and osteoprotegerin in the group of preclinical RA patients, compared with a control group of healthy individuals. Specifically, P1NP increased by 5 ng/mL and osteoprotegerin increased by 4 pmol/L (Ann. Rheum. Dis. 2010 Oct. 18 [doi:10.1136/ard.2010.135723]).
Three blood samples taken 1, 2, and 5 years prior to the onset of symptoms were identified for 47 patients with RA; two samples were collected from 18 patients and one sample was collected from 14 patients. The individuals had been blood donors prior to developing the disease.
The study was funded by the Dutch Arthritis Association. The authors reported that they had no competing interests.